A boy and a girl are sitting on the porch.
"I'm a boy," says the child with black hair.
"I'm a girl," says the child with red hair.
If at least one of them is lying, who is which?

What word does this rebus represent?

meta meta
meta meta

I sleep during the day and fly at night, but I have no feathers to aid my flight. What am I?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

How many letters are in the alphabet?

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

I ask Joseph to pick any 5 cards out of a deck with no Jokers.

He can inspect then shuffle the deck before picking any five cards. He picks out 5 cards then hands them to me (Jack can't see any of this). I look at the cards and I pick 1 card out and give it back to Joseph. I then arrange the other four cards in a special way, and give those 4 cards all face down, and in a neat pile, to Jack.

Jack looks at the 4 cards i gave him, and says out loud which card Joseph is holding (suit and number). How?

The solution uses pure logic, not sleight of hand. All Jack needs to know is the order of the cards and what is on their face, nothing more.

What has many teeth, but cannot bite?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

I have an eye but still cannot see.

Who am I?